Safety device for elevators.



PATENTED OCT; 27, 1903 I. H. WILSON. SAFETY DEVICE FOR ELEVATORS.

APPLICATION IIIJED JULY 17, 1902.

N0 MODEL.

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in detail, referring to the accompanying draw-' UNITED STATES Patented October 27, 1903;

PATENT OFFICE.

SAFETY DEVICE FOR ELEVATORS.

SPECIFICATION forming part of Letters Patent No. 742,542, dated October 27, 1903.

Application filed July 17,1902. $erial N0. 115,901. (No model.) i I To all whom, it may concern.-

Be it known that I, FRANKLIN H. WILSON, a citizen of the United States,residing at Parkesburg, county of Chester, and State of Pennsylvania, have invented a certain new and useful Improvementin Safety Devices for cation.

My invention relates to a new and useful improvement in safety devices for elevators,

and has for its object to provide a device which, working in conjunction with stationary ratchets secured upon each side of the elevator-shaft, will instantly catch and hold the elevator should the cable break or be unduly slackened from any accident whatso ever.

With this end in view this invention con sists in the details of construction and combination of elements hereinafter set forth and then specifically designated by the claims.

In order that, those skilled in the which this invention appertains may understand how to make and use the same, the construction and operation will now be described ings, forming a part of this specification, in which- Figure 1 is a vertical section through my improved apparatus, showing the same applied to an elevator and showing the parts in their normal position; Fig. 2, a similar view to Fig. 1, showing the operating parts in the position they would assume when the cable is either broken or unduly slackened; Fig.

3, a horizontal section taken on the line 3 3 of Fig. 2.

A represents the car or cage forming the elevator, and B represents the guides extending vertically up each side of the elevatorshaft, and upon each side of these guides are arranged ratchet-teeth O.

D is my improved safety appliance,which is arranged above the cage of the elevator and is connected thereto by means of yokes E,which are secured to the cage and pass up each side and over each end of the appliance D, and pins F extend up from each end of the safety appliance D through the top of the yoke E, and springs G are coiled around the pins and interposed between the top of the appliance D and the under side of the top of the yokes E,

art to' and as the cable II is connected to the safety appliance the cage is suspended from the ap pliance and connected thereto by a yielding connection furnished by the springs G. Thus if *the car is stopped suddenly the springs will give, so as to lessen the jar.

' I represents horizontal sliding bolts or latches guided in each end of the appliance D, and these bolts or latches are forked upon their outer end, as shown in Fig. 3, so as to straddle the guideways B.

J represents arms pivoted at their lower ends to the inner ends of the bolts or latches I and at their upper ends to the framework of the appliance D.

K represents two links, one end of one being pivoted to one of the arms J intermediate of its two ends and one end of the other link K being pivoted to the other arm J intermediate of its two ends, the other two ends of the links K being pivotedtog'ether at the center L, and journaled uponthis pivot L is a grooved roller -M, around which the cable H passes. The pivot L passes through the framework of the appliance D upon each side, and this framework is provided with a vertical slot N, sov as to cause the pivot L to move up and down in a vertical line. Thus it will be seen that the links K form a togglejoint, so that when the cable H is taut the pivot L will be raised to its highest limit'and stopped by the termination of the slot N, and thus through the links K the arms J will be swung'nward, which will pull the bolts I inward, and thus hold the two prongs of each of the bolts I out of engagement with the ratchetteeth 0, located nponeach side of the guide- 0 represents springs, one end secured to the ends of the appliance D and the other end of the springs being secured to the arms J.

These springs exert a tendency to always force the bolts I outward. Therefore should the cable H be unduly slackened or be broken the springs 0 will then be allowed to act to instantly force the bolts I outward, so that the two prongs of each of the bolts will come into engagement with the ratchet-teeth C, and therefore catch the elevator and hold it against falling.

While I have shown the cable H as passing around the grooved roller M, it is obvious that one end of the cable could be secured around the roller and the apparatus would then work in exactly the same manner.

The advantage of myinvention is that the operating parts are exceedingly few in number and very simple; but the apparatus is very efficient in working, as the springs 0 will be strong enough to throw the bolts outward as soon as the cable is broken or unduly slackened, and of course the bolts then coming in contact with the stationary ratchetteeth will stop the car instantly, and the buffer-springs G will relieve the jar, and thus prevent injury to the persons in the cage of the elevator.

Of course I do not wish to be limited to the exact construction here shown, as slight modifications could be made without departing from the spirit of my invention.

Having thus fully described my invention, what I claim as new and useful is 1. In a device of the character described, an elevator-cage, a safety appliance from which the cage is suspended, bufier-springs interposed between the cage and safety appliance, guideways running vertically of the elevator-shaft, ratchetteeth formed upon each side of said guideways, horizontallysliding forked bolts guided in the framework of the safety appliance and normally held out of engagement with the ratchet-teeth, a cable for supporting and moving the elevator, a movable connection connecting each of the sliding bolts, said cable so connected to the movable connection as to hold the bolts normally withdrawn, and springs for shooting the bolts outward when the cable is broken or slackened, as and for the purpose specified.

2. In a device of the character described, a cage or car, a framework arranged above the car, yokes secured to the car and passing up upon each side and over the ends of the framework, buifersprings interposed between the upper surface of the framework and the yoke, guideways extending vertically of the elevator-shaft, ratchet-teeth secured upon each side of the guideways, horizontally-sliding bolts guided in the framework and extending outward from each end thereof, the outer ends of said bolts forked so as to straddle the guides, a toggle-joint, the two members of which are connected to the sliding bolts and also connected together at the center, the framework provided with slots for guiding the central pivot of the toggle-joint vertically, a cable secured to the central pivot of the toggle-joint, and springs for shooting the bolts outward into engagement with the ratchet-teeth when the cable is broken or slackened, as and for the purpose specified.

3. In a device of the character described, an elevator cage or car, a framework arranged above the cage or car, yokes extending upward from the cage and passing up upon each side and over the ends of the framework, pins extending upward from the framework and passing through the yoke to form guides, buffer-springs surrounding the pins and interposed between the framework and the yokes, guides extending vertically of the elevator-shaft upon each side, ratchetteeth arranged upon each side of the guides, horizontally-sliding bolts guided in the framework and adapted to engage the ratchet-teeth when thrown outward, arms pivoted at their upper ends to the framework and at their lower ends to the bolts, two links each connected to one of the arms, bothof said links connected together upon a common pivot, a grooved roller also journaled upon said pivot, the framework provided with vertical slots through which the pivot passes, a cable for elevating and lowering the elevator-car passing around said grooved roller, and springs arranged to shoot the bolts outward when said cable is slackened or broken, as specified.

In testimony whereof I have hereunto affixed my signature in the presence of two subscribing witnesses.

FRANKLIN H. WILSON.

Witnesses:

H. B. HALLOCK, L. W. MORRISON. 

